1. Field of the Invention
The present invention relates generally to optical fiber connectors or termini, and, more particularly, to an optical fiber terminus which can transmit relatively high power optical energy without being damaged.
2. Description of Related Art
An optical fiber connector or terminus is a device for locating the ends of two fibers that have had their respective ends faced off at 90 degrees to their longitudinal axis and are precisely aligned in order to enable the efficient transfer of light energy across the junction. Specifically, a well known present day terminus includes a ceramic or metal ferrule having an appropriately dimensioned opening in which one of the fibers is located, with a pair of the ferrules being received within an alignment cylinder for holding the fiber ends in proper end spaced relationship. In a certain other known terminus, the ends of the fibers are coupled via one or more lenses.
Where relatively high energy optical signals (e.g., 0.5 Joules) are used there is a tendency for the fiber and adjacent terminus parts, such as the ferrule, for example, to become discolored and physically damaged from the conversion of the light being transmitted along the fiber into heat. In explanation, an optical fiber typically includes an outer buffer coating that protects the core and cladding against contact damage. When the fiber has an end portion assembled into a known present day terminus ferrule, it first has the buffer coating removed from the end portion. Accordingly, when a light signal of a energy level equalling about 0.5 Joules or higher passes through the terminus junction a part of the light energy is absorbed by the ferrule and converted to heat, which has been found sufficient to damage the terminus.
In the past these ferrules have been made of either stainless steel or ceramic, the two materials which were the only materials known to possess the desired properties of good heat tolerance as well as being able to be made in precisely dimensional configurations required and manufacturable for a relatively reasonable cost. When the power of light signals being transmitted along the fiber, and across connector junctions, increased to the power levels indicated it has become necessary to seek alternative constructions that can withstand high power transmissions.